Deep Sea Mysteries: The Greenland Shark

By Virginia Rose Whalen

Podcast Transcript

When you look deep into the ocean, the world you will see is colder, darker, and slower.

The species who live there have to adapt to these harsh environments by moving in slow motion. Their metabolism slows down, and their growth – even slower. They live a life so different from our own, it’s almost unimaginable.

Living the slow life can also mean surviving for a really long time. Take the Greenland Shark (Somniosus microcephalus) for example. This species resides deep in arctic waters, typically reaching more than 13 feet in length. A 2016 study discovered that these sharks can live to be a whopping 400 years old, and don’t reach reproductive maturity until at least 150. The authors of the study used radiocarbon dating on the eye lenses of deceased specimens in order to determine their age. It was also estimated that the sharks grow less than a centimeter a year, which contributes to their longevity.

Despite being so slow and so old, Greenland Sharks are considered to be the top predators of their food chain. Though they were long assumed to only scavenge for things that have already died, a 2013 study found that they are actually capable of catching live prey. They eat things like Atlantic cod, wolffish, and even harbor seals.

We still have a lot to learn about how deep sea fish like the Greenland Shark live. With most of the ocean left unexplored, there are almost certainly more fascinating species out there.


Nielsen, J., Hedeholm, R. B., Heinemeier, J., Bushnell, P. G., Christiansen, J. S., Olsen, J., Ramsey, C. B., Brill, R. W., Simon, M., Steffensen, K. F., & Steffensen, J. F. (2016). Eye lens radiocarbon reveals centuries of longevity in the Greenland shark (Somniosus microcephalus). Science 353(6300), 702-704.

Nielsen, J., Hedeholm, R. B., Simon, M., & Steffensen, J. F. (2013). Distribution and feeding ecology of the Greenland shark (Somniosus microcephalus) in Greenland waters. Polar Biology 2014(37), 37-46.


2,000 Year Old Sustainable Fisheries

Figure 1: Salmon bone samples (Credit -Dan Robitzski for The Scientist)

Prior to European colonization, the indigenous communities of the Pacific Northwest practiced sustainable fishing techniques for thousands of years. A recent collaboration between scientists at Simon Fraser University and the Tsleil-Waututh nation revealed how these Coast Salish peoples maintained a sustainable chum salmon (Onocorhynchus keta) fishery 2,000 years ago (Robitzski 2021).

A team of scientists and archeologists from the university designed this project for the Tsleil-Waututh nation to validate historical records from the Port of Vancouver. Using PCR techniques, scientists were able to extract the DNA from salmon bone samples (Figure 1)  that had been collected from four different historical sites along the northeast coast of Vancouver (Morin et al 2021). They discovered that at two of the four sites, the bones were overwhelmingly male. The other two sites had a more balanced mix of male and female salmon remains.

With just the raw DNA data, it was at first unclear whether this uneven distribution of sexes was intentional or not. So, the university scientists then turned to members of the Tsleil-Waututh Nation to better understand the nation’s historic fishing practices. These members confirmed that the Coast Salish inhabitants did prefer male salmon, because they were larger and provided more food (Robitzski 2021). Furthermore, these fishermen could easily distinguish between the sexes due to the coloration and large front teeth of males (Figure 2).

Figure 2: Spawning male (top) and female (bottom) chum salmon (original artwork by Dorian Noël 2020).

Together, the scientists and Tsleil-Wauthuth nation concluded that this data suggests male salmon were also selected because of the sustainable benefits. It is likely fishermen realized that male fish can fertilize the eggs of multiple females, so fishing selectively for males would not deplete the overall salmon population. Therefore, the Coast Salish peoples were able to sustain a healthy chub salmon fishery.


With the current world human population on the never-ending rise, overfishing continues to become a pressing issue. It is key that we continue studies like this one in order to learn from the sustainable practices of our ancestors.




Morin, J., Royle, T.C.A., Zhang, H. et al. Indigenous sex-selective salmon harvesting demonstrates pre-contact marine resource management in Burrard Inlet, British Columbia, Canada. Sci Rep 11, 21160 (2021). 


Robitzski, Dan. (2021, November 29). 2,000-year-old salmon DNA reveals secret to sustainable fisheries. The Scientist Magazine®. Retrieved November 30, 2021, from  

Invasive Sea Lamprey in the Great Lakes


Satellite image of the Great Lakes taken April 24, 2000. Photo courtesy of NASA/Goddard Space Flight Center


The North America Great Lakes basin is the largest surface freshwater resource in the world, having formed approximately ten thousand years ago from glacier activity and supporting over 120 native fish species. They are a vital resource providing water for consumption, recreation, power, along with fisheries for harvest (US Fish & Wildlife Service, 2021). However, due to human activity during the 1800s and early 1900s,  the Great Lakes have been invaded by numerous invasive (exotic organisms that cause harm to the surrounding environment) species with one of the most prominent being the invasive Sea Lamprey (Petromyzon marinus).

Sea lamprey in a tank
Sea Lamprey (Petromyzon marinus) in a tank. Photo courtesy of Joanna Gilkeson of the US Fish & Wildlife Service.

The Sea Lampreys are a parasitic jawless fish that are native to the Atlantic Ocean. During the 1800s they made their way into the inland Great Lakes basin via manmade locks, shipping canals, and ballast water as humans navigated the region. They were first observed in Lake Ontario during the 1830s, Niagara Falls was a natural barrier to their dispersal however the Welland Canal constructed in the early 1900s allowed them to access the other Great Lakes with being spotted in Lake Erie in 1921 and then the other lakes later (Sullivan et. al., 2003) (US Fish & Wildlife Service, 2021).

Their introduction caused major destruction to the Great Lakes ecosystem, significantly reducing native fish populations especially the Lake Trout fishery. With a little over 1% of surface water on Earth being freshwater, it is vital to protect and preserve the health of these vulnerable ecosystems for humans and fishes alike.

Sea Lamprey Lifecycle

The Sea Lamprey lifecycle despite originating from the Atlantic Ocean have adapted since their introduction to the Great Lakes systems possibly due to their anadromous (migrate from sea/ocean to rivers to spawn) nature.

Sea Lamprey lifecycle. Image courtesy of the Great Lakes Fishery Commission

The Sea Lamprey grow in Great Lake tributary streams as larvae that filter feed on detritus and plankton for approximately 3-10 years (Great Lakes Fishery Commission 2a, 2021). They then metamorphize developing eyes along with oral disks and tongues with pointed teeth. They migrate downstream towards the lakes where they become parasitic juveniles, feeding on the blood of host fish for 12-18 months. As the winter months come, they stop feeding and migrate towards spawning stream where they become sexually mature adults and reproduce during the spring and early summer seasons. Once they spawn, producing up to 100,000 eggs in a spawning event, they die soon afterwards.



Sea Lamprey Impact on Great Lake Fisheries

The Sea Lampreys are most dangerous to other fish populations during their parasitic juvenile stage once they enter into the Great Lakes. Sea Lampreys attach to fish using their suction cup mouths, gripping onto the fish by digging their teeth into the body. They then feed on the fish’s body fluids by secreting an enzyme that stops blood clotting allowing them to continually feed on a host. As there is no co-evolutionary link in the Great Lakes as with fish in their native Atlantic Ocean, Sea Lamprey individuals can kill up to 40 pounds of fish during their 12-18 month feeding stage (Great Lakes Fishery Commission 2c, 2021).

sea lamprey sucking on the side of a trout
Sea Lamprey sucking on the side of a trout. Illustration courtesy of Michigan Department of Natural Resources.

Sea Lampreys mainly feed on large fish species such as Burbot, Lake Sturgeon, Whitefish, Chub, and Lake Trout (Salvelinus namaycush) which has drastically fish populations present in the basin. The Sea Lamprey invasion at its peak resulted in a drastic reduction of Lake Trout fishery harvest with the average catch being 300,000 pounds by the early 1960s, a drastic reduction from the 15 million pounds caught in the past (Great Lakes Fishery Commission 2c, 2021).

Once management programs were established in the 1970s and 1980s the suppression of Sea Lampreys was near immediate, with Lake Trout populations along with other species recovering however Sea Lamprey numbers have rebounded primarily in Lake Erie due to suspected migration from untreated larval populations (Sullivan et. al., 2003).

Current Management Efforts

Efforts are being made to reduce the invasive Sea Lamprey population in the Great Lakes basin and so far is the only worldwide example of a successful invasive aquatic vertebrate  control program on an ecosystem-wide scale (Great Lakes Fishery Commission 2b, 2021).

Management program focus on the portion of the Sea Lamprey lifecycle in tributaries as larvae. Taking advantage of this information, biologists assess tributaries that contain larval Sea Lampreys to determine when and where pest control should be administered.

There are numerous methods that are utilized with the two most effective being lampricides and barriers.

U.S. Fish & Wildlife Service Sea Lamprey control agent conducting a lampricide application on a Great Lakes tributary. Photo courtesy of the Great Lakes Fishery Commission

Lampricides are the primary method used in targeting Sea Lamprey larvae in management programs. The lampricide TFM (3-trifluoromethyl4′-nitrophenol) and Bayluscide are most effective compounds found in controlling larvae after extensive testing. TFM kills larvae by disrupting energy metabolism of the Lamprey preventing them from developing further and migrating to the lakes. Bayluscide is combined with TFM in order to limit the amount of TFM required in tributary treatments. The most beneficial aspect of this method is that the compounds are lethal towards Sea Lamprey while being relatively harmless to other organisms.

Low-head barrier in tributary creek in Indiana. Photo courtesy of the Great Lakes Fishery Commission

Barriers prevent Sea Lampreys from migrating to spawning gravel and soft substrate types for larvae to burrow. Barriers function by stopping adult Sea Lampreys from accessing spawning grounds and limiting their habitat distribution. This method is effective with low-head barriers and trap and sort fishways  designed to allow jumping and non-jumping fish species to still pass while Sea Lampreys are trapped.






1. Sullivan, W. P., Christie, G. C., Cornelius, F. C., Fodale, M. F., Johnson, D. A., Koonce, J. F., Larson, G. L., McDonald, R. B., Mullett, K. M., Murray, C. K., & Ryan, P. A. (2003). The Sea Lamprey in Lake Erie: A case history. Journal of Great Lakes Research, 29, 615-636.

2a. Great Lakes Fishery Commission. (2021). Sea Lamprey lifecycle. Available at (Last accessed 1 December 2021)

2b. Great Lakes Fishery Commission. (2021). Sea Lamprey control in the Great Lakes. A remarkable success!. Available at (Last accessed 1 December 2021)

2c. Great Lakes Fishery Commission. (2021). Sea Lamprey: A Great Lakes invader. Available at (Last accessed 1 December 2021)

4. U.S. Fish & Wildlife Service. (2021). Sea Lamprey control program. Available at (Last accessed 1 December 2021)

5. Michigan Department of Natural Resources. (2021). Sea Lamprey: Vampires of the Great Lakes. Available at,4570,7-350-79135_101864-549964–,00.html. (Last accessed 1 December 2021)

Delta smelt

The delta smelt is a species that lives in California’s Delta, where half of California’s fresh water is moved through and used for agriculture, industry, and residents.  The delta smelt is sensitive to changes in it’s habitat and it’s decline in the delta is a concern for the smelt and the overall health of the California Delta.  The delta smelt is a concern because the delta smelt is a keystone species in the delta and it’s decline is an indicator on the overall health of the delta.  Many other fish that have been introduced in the delta and are native are also declining in the delta as well.  It is likely that the smelt is decline is due to a combination of factors such as the loss of freshwater flowing, water diversion, introduces species, and pollution.  Fortunately, when conditions are favorable as it was seen in 2011, the smelt’s population could rebound and it shows that the health of the delta is recovering.

Unfortunately, the delta smelt also lives in a region with a high amount of agricultural activity and it’s protection has caused a lot of controversy.  I have been to California many times and I have seen many signs saying “Stop the Congress Made Dustbowl.”   Because one of the reasons the delta smelt is endangered is because of the lack of freshwater flow and the delta getting more salty, and to help the smelt waterflow for the smelt was increased, which reduced the freshwater that could be used in agriculture.  Many people think that the increased waterflow for the smelt is a waste of fresh water and it is solely for the smelt.  The increase in freshwater flowing will also be beneficial to the delta as a whole because the flow of freshwater also reduces the salinity in the delta.

Although the delta smelt is commonly blamed for the lack of water that can be used in agriculture, the loss of the delta smelt is due to a larger environmental issue.  The loss of freshwater flow in the delta will likely cause a decline in other species that live in the delta such as the longfin smelt and the chinook salmon.

(Picture Renee Reyes all rights reserved)

Farmers vs. Fish: The Story of Delta Smelt

Devil’s Hole Pupfish

The devil’s hole pupfish is possibly one of the rarest fish in the world with 65 individuals being counted as of 2013.  The devil’s hole pupfish also lives in extreme circumstances for fish by living in caverns that reach 93 degrees in The Mojave Desert.  The temperatures and oxygen levels are lethal for most fish species but the devil’s hole pupfish has been found to thrive in the conditions in the past.  The devil’s hole pupfish have one of the smallest range of any vertebrate, living in an area that is smaller than most people’s office.

Unfortunately, the devil’s hole pupfish has been declining from 550 individuals being counted when the counts started to numbers as low as 35 individuals.  Previous attempts to establish a captive population have failed until recently.  When a captive population was being attempted to be made, there was a species of diving beetle that was previously found in the caves of the pupfish and wasn’t thought to be a big deal they were in the tank with the captive population.  It was later found out that the diving beetle was eating the pupfish eggs and larva and causing the previous attempts to establish a refuge population to fail.  A successful refuge population has now been established and there are now 50 individuals in the refuge population and in 2018, devil’s hole had a population of 187 devil’s hole pupfish.

Photo by Brett Seymour

Lake Erie Walleye Boom!

Figure 1: One of the many nice “Erie Eyes” I’ve caught over the last couple of years as a novice Walleye angler.

Lake Erie has been known as “The Walleye Capital of the World” by many anglers for years due to it’s historically excellent Walleye (Sander vitreus) fishery. This title was especially popular in the 2000’s when Walleye numbers and size were reaching record highs due to very successful hatches.

Many anglers I’ve spoken to look back on the late 2000’s with nostalgia for the bountiful harvests and memories made spending the day catching Walleye with friends and family. Recently however, anglers have been given another chance to enjoy some of Lake Erie’s finest fishing due to a now booming Walleye population. During 2021, it is estimated that the number of two year old Walleye, which are reaching the keeper size limit of 15″ minimum, will be close to 100 million fish (Ohio Division of Natural Resources, 2021). These numbers are quickly approaching those seen during the hay day of Erie’s Walleye fishing when it first earned its notoriety as one of the best places to catch Walleye worldwide.

But how do you catch these fish?

Anglers are seeing very high success rates with variety of lures and techniques and “Walleye catches per hour” are hitting some of the highest rates ever recorded by fisheries biologists with the Ohio Division of Wildlife (Ohio Division of Natural Resources, 2021). Speaking with a local bait shop employee or viewing various fishing forums or pages on Facebook can give you a great idea on how to learn what lures and where Walleye are being caught. Throwing nightcrawler harnesses and deep diving crankbaits behind the boat has yielded great results for many in the past and continues to perform exceptionally well today. Typically, throwing brighter colors like gold or white when water clarity is high works best and throwing darker colors like black in the warmer months when algal blooms occur yields the best results (Nieman et al., 2020).

No boat? No problem!

If a boat is unavailable, worry not, there are plenty of charter captains on the lake that are glad to treat their clients to very successful days on the water at fair prices. They take care of setting up the gear, netting the fish, and many also offer services to clean your catch for you! Additionally, many anglers can enjoy amazing Walleye fishing during the Spring spawning run. Walleye school up in the creek and river tributaries of the lake where they are readily accessible to wade fisherman and bank anglers alike using all kinds of lures.

Outlook of Walleye fishing looks great!

Due to the high numbers of fish, many first time Erie fisherman and veteran anglers alike are making the trip up the lake and are finding success. Walleye fishing should be good for years to come and now is the time to go if you ever thought about fishing Ohio’s great lake. Be sure to purchase an Ohio fishing license and familiarize yourself with the rules and regulations of the water before fishing. Also remember, Lake Erie is also known as the Seasickness Capital of the World so take some anti nausea medicine like Dramamine before heading out onto the water. Good luck!

Get your license here:


Nieman, C. L., Bruskotter, J. T., Braig IV, E. C., & Gray, S. M. (2020). You can’t just use gold: elevated turbidity alters successful lure color for recreational Walleye fishing. Journal of Great Lakes Research46(3), 589-596.

 Ohio Division of Natural Resources. (2021). Get Your Gear Ready for Lake Erie Walleye Fishing.

Too Much Lead You’re Dead

Michigan, is an absolutely gorgeous state and as an Ohio State football fan I would never give that state a compliment unless it were true. Michigan is surrounded by four out of the five Great Lakes: Huron, Michigan, Superior, and Erie. Water health is an ongoing issue in this state, with the Flint crisis being the most famous. However, with updated EPA regulations and more rigorous testing for lead in drinking water more and more cities in Michigan as well as in Ohio could be looking at dangerous lead levels that previously went unnoticed. 

Now most of us know how dangerous high lead levels are for humans. But for those of us that don’t the CDC states that common ailments that occur with high lead exposure include anemia, weakness, and both kidney and brain damage. But what does lead exposure mean for fish that spend 100% of their life swimming in high levels of lead?

Greater concentrations of lead in water and bottom substrate can be dangerous for fish. Water with higher concentrations of lead can lead to acute lead toxicity. Acute lead toxicity damages the gill epithelium which is the thin tissue on the outside of gills that allow fish to breather underwater. Once the gill epithelium is affected this causes death by suffocation. Additionally, high lead levels in water changes the chemical makeup of their blood. This then leads to damage to the kidneys, adrenal glands, liver, spleen, and pancreas. Furthermore, a fish’s nervous system can be seriously damaged with too much lead exposure. 

Excess amounts of lead in water is not only a humanitarian crisis but an environmental crisis as well. More attention needs to be focused on the lead crisis that is currently happening.


Trophy fish are giant fish of different species well sought after by anglers for their size. These fish tend to either  hang on someone’s wall after being caught or posted to their dating profile.  

However, trophy fish are about to take on a whole new definition thanks to a new fad called micro-fishing. Microfishing is fishing for small fish that are not normally pursued by anglers. Some popular microfishing fish include minnows, dace, darters, and sculpin. Here in Ohio we have all four of the  popular genera in our rivers, lakes, and streams!

In order to get into microfishing you’ll need to purchase a tiny hook, light line,  a crappie rod, and your bait (worms work great)! Additionally, in order to Microfish you need some pretty good eyesight since this sport involves sight fishing. This website goes into more detail for all your microfishing needs or Tenkara Bum for gear. 

Microfishing originated in Japan with the fishing for Tanago (Bitterling). The purpose of tang fishing is to catch as small of a fish as possible. Many Microfisher anglers in the U.S. are pursuing different species not just for their size but also rareness. 

Microfishing has the potential to inspire awareness for fish species that are often overlooked. Microfishing can also show citizens in Ohio the many amazing fish species in our streams, rivers, and lakes and bring about further protection for our fragile waterways.

Lake Erie Poem

Lake Erie, shallow as can be,

Fish abundance, far as the eye can see,

Memories created, in the fondest of ways,

Illuminating sunrises reflected on crashing waves.


A grim foe, threatens tranquility,

Algae blooms, green as itchy grass,

Toxic poisons, suffocating grasp,

Great water health, of the past.


Farm fields hosting banquets,

Handed on a silver platter by Summer rains,

Sponge like wetlands saving the day,

Helping organisms carry on their way.


Over the years, Lake Erie has struggled with toxic algal blooms affecting the environment and even the local economy.  I wanted to create a short poem for this important topic to spread awareness of how truly destructive these harmful algae blooms are on surrounding ecosystems. These blooms are known to suffocate many different species of fish and other organisms in Lake Erie by depleting oxygen in the water (1). The major reason for these algal blooms is agriculture runoff from surrounding landscapes that eventually dumps potent concentrations of Phosphorus and Nitrogen into Lake Erie (2). These nutrients act as a food source for algae and causes them to exponentially grow into the blooms we see across the lake.

In the poem, I quickly mention the idea of wetlands because it’s believed they are a possible remedy for nutrient overload dumping into Lake Erie (3). Wetlands are fantastic at adsorbing nutrients, similar to a sponge, in any water that flows through them because of roots from surrounding dense vegetation. A large resource for algal blooms can then be greatly reduced by restoring wetlands in areas with high nutrient runoff before they reach Lake Erie.



1) National Weather Service. Lake Erie Harmful Algal Bloom: About. National Oceanic and Atmospheric Administration. Retrieved from:

2) Kozacek, C. (2014) Cause of Lake Erie’s Harmful Algal Blooms Gains More Certainty. Circle of blue. Retrieved from:

3) Mitsch, W. (2017) Solving Lake Erie’s harmful algal blooms by restoring the Great Black Swamp in Ohio. Ecological Engineering. (108): 406-413





Walleye in Aquaculture

Like to catch Walleye, but are concerned about overfishing?

Fear no more! Aquaculture is here to save the day.

Aquaculture is the world’s fastest growing food production industry. Many species are of aquaculture interest, including Walleye (Sander vitreus), Yellow Perch (Perca flavescens), Rainbow Trout (Oncorhynchus mykiss) and many more. Aquaculture is defined as the raising of aquatic organisms for food. The industry of aquaculture often rears sport fishes—such as the Walleye—for the purposes of stocking them. Once they are stocked, anglers catch them and eat them. Walleyes are now one of the most sought-after sport fishes, and they are found in 32 percent of freshwater ecosystems in North America. The North Central Aquaculture Center previously identified Walleye as one of the most promising aquaculture species.

Great Lakes populations of Walleye have been overfished in the past, resulting in population declines in areas of the Great Lakes. States have implemented strategies to prevent population decline, such as habitat protection as well as walleye rearing and stocking. Rearing and stocking Walleye can help keep the population at a healthy level and keep Walleye in the Great Lakes for many years to come. Walleye can be stocked as juveniles; from there they will continue to grow in the wild until they are of catching size. The U.S Fish and Wildlife service has stated that climate change has begun to affect Walleye habitat distribution. The displacement of Walleye by warm water species may change their range and population. The culturing of Walleye for stocking purposes may help to mitigate this issue.

So how is it done?

Walleye are often bred in aquaculture facilities and kept there until they are of stocking size. They are often fed commercially available foods. Typically, they are kept in large tanks with colder water, in order to best mimic their natural habitat. Tank size will vary based on the aquaculture facility or lab. In Dr. Dabrowski’s lab on the OSU campus, we keep our juvenile Walleye in 400L tanks. Here is a photo showing where they are kept!



The Utility of Zebrafish

Zebrafish are a small tropical species in the Cyprinidae family, and they are native to regions in South Africa.

Have you ever wondered why Zebrafish are often used in medical research?

It turns out that Zebrafish are a model organism, and share a lot of similarities to humans! We actually share 70% of our genes with Zebrafish. They have a lot of the same physical characteristics as us, such as a heart, spinal cord, eyes, kidneys…the list goes on. Zebrafish have also been useful for studying human diseases. Since Zebrafish share a lot of the same characteristics, changes in human organs as a result of disease will also appear in Zebrafish organs as well. They have also been used for toxicology studies, such as how certain substances or drugs affect their physiology.

Zebrafish are useful for understanding areas of ecology as well. Lots of genetic experiments have been performed with Zebrafish. Since they are a model species, methodology used in genetic experiments can also be applied to other species. A lot of people may wonder about the other benefits of Zebrafish, aside from them being a model species. First, they are quite small. This makes them efficient to keep in research labs, especially where space is often limited. They are quite easy to handle, hardy, and are easy to provide proper husbandry for. Also, females are quite fecund and will produce many eggs per spawning event. This is useful for when many eggs or embryos may be needed to run an experiments. Unlike some fish, Zebrafish in captivity do not have a spawning season. Spawning can be induced anytime, which is very useful for experimentation and research purposes. Lastly, in vitro fertilization (fertilization outside the body) can be done with Zebrafish, making it very easy to control fertilization and study development.

Here’s a photo of a Zebrafish:

Here’s a photo of a Zebrafish embryo developing under the microscope (this is at the 8 cell stage!)


The Recovery of the Lake Trout Species in Lake Erie

The lake trout (Salvelinus namaycush) was once a thriving, native species to Lake Erie. However, after numerous effects caused its decline and ultimate demise, it has been a difficult process of attempting to restore the species back to what it once was.

Lake Erie lake trout

Lake trout Lake Erie Capt. Pete Alex Capt. Mike Johannes

Photo credit: The Buffalo News, courtesy of Bill Hilts Jr.

Lake trout was a prevalent species in the fish community of Lake Erie. This changed after commercial fishing moved into Lake Erie in the 1700s. The impacts of fishing only worsened in the 1800s when commercial fishing intensified. The intensification was caused by the increase in waters that were fished, including deeper waters. Additionally, gill nets came to be used as well as larger fishing vessels, all of which led to higher catch counts, therefore harming the lake trout population to a point of decline. The impact was so great, that the average annual harvest of lake trout in the late 1800s-1900 was more than 22,000 pounds.

Once managers started noticing what was happening in Lake Erie with the lake trout population, there was an attempt for management strategies to be implemented. One of these strategies was the regulation of the fisheries, which in the beginning was not very successful. Another strategy was to stock the lake with lake trout, which began back in 1879.

As time went on, even more negative factors were affecting the lake trout species. The first of these negative factors was the alteration of Lake Erie due to pollution and eutrophication. These negative effects altered the lake water, and therefore the lake trout’s habitat, which caused multiple issues, including declines in reproductive success. A second negative factor that began influencing the lake trout population was an invasive species, the sea lamprey (Petromyzon marinus), which was considered to be a parasite to the lake trout.

A sea lamprey attached to a lake trout

lake trout lamprey

Photo Credit: International Joint Commission, credit: Marc Gaden, GLFC

It is believed that the complete depletion of the lake trout occurred sometime soon after 1965. Since then, various agencies have worked together to attempt the recovery process of the species in Lake Erie, including the New York Department of Environmental Conservation and the Pennsylvania Fish and Boat Commission. Management strategies to recover the species have included control on sport fishing mortalities, prohibition on the commercial fishing of lake trout in Lake Erie, and continued treatment for reducing the sea lamprey population.

Management strategies have shown some positive outcomes on the abundance of lake trout in Lake Erie thus far, as the annual survival of the lake trout has been increasing. As time goes on it is important that managers continue to keep up with maintenance stocking and that budgets remain in place for both stocking and the treatment of the sea lamprey. Things are looking up and it does look like the future for the lake trout in Lake Erie is bright.


Literature Cited

Floyd C. Cornelius, Kenneth M. Muth, Roger Kenyon, Lake Trout Rehabilitation in Lake Erie: A Case History,
Journal of Great Lakes Research, Volume 21, Supplement 1, 1995, Pages 65-82, ISSN 0380-1330,


Japanese Artist Finds His Muse in Fish

Artist Yusei Nagashima’s muse is fish. His fascination began as a child and has manifested itself into detailed watercolor paintings of a diversity of species. He claimed that he was, “captivated by the form of the fish,” when he was young and, “how it carried itself in the water, the sparkle of its eyes and scales; the lively movements of its muscles when it was caught, its intimidating, expression as its throat swelled.”(Weeks). At age eight, his first interest in fish was peaked during a visit to a tropical fish store, where he saw baby piranhas. He expressed the contrast in the way that they are typically viewed as, being vicious and brutal, compared to the way he viewed them, as “delicate and beautiful.”(Gestalten). From that point forward, he found his art focusing on fish over everything else.

Yusei’s interest in fish does not stop in his artwork. He enjoys fishing and reflects on fond memories of fishing with his father as a child. He expressed the mixture of emotions that he felt during one particular experience where he lost his favorite rod to a large fish while angling in the ocean. He recalled being disappointed and frightened in the moment but when his father caught a fish that happened to be the one attached to his rod, he realized how impressive of an experience that was, “during which I felt both great fear of and respect for the depths of the ocean.”(Gestalten).

Three years ago Yusei began posting one painting each Friday on his blog (Yusei Nagashima). On his blog you are able to view his watercolor works that encompass a wide diversity of fish. He feels that his art can be an aid in teaching people about the importance of not only fish, but the natural world as a whole. “Nature is something that we must protect…We must think about our position as humans in nature and we should live alongside nature. I think fish and fishing reveal such a relationship.”(Gestalten).

Gestalten US Shop. “Meet Yusei Nagashima of the Fly Fisher.” Gestalten US Shop,

Weeks, David, et al. “Japanese Artist Creates Delicate Watercolor Paintings of Fish Every Week.” My Modern Met, 16 June 2016,,his%20beautifully%20detailed%20watercolor%20paintings.

Yusei Nagashima,

Fishy Memes and What They Mean

I want to fart so hard

Despite what this meme says, this puffer fish does not have to fart. What causes these fish to look like they have really bad gas? It is a defense mechanism that they perform when threatened. The goal of inflating is to multiply the size of the fish and to present their spines. This makes the puffer fish more difficult to bite which makes them less appealing to predators. It’s not a fart, its fear! (Seattle Aquarium, 2021).

“Why Do Pufferfish ‘Puff up’?” Seattle Aquarium,,very%20appetizing%20to%20a%20predator.&text=Most%20puffers%20are%20toxic%20to%20eat.



They gave me a friend once…

Betta fish are infamous for being solitary and territorial creatures that do not get along with others. What many people do not know is that there is a reason that betta fish are so prone to fight. In the 1800s people discovered these fish and found that some of them were very aggressive and prone to fight, so they began to be bred for their aggression, for the purpose of betta fighting (Bryan, 2018). As a result, aggression has been maintained in their genetic makeup to this day.

Bryan, et al. “Why Do Betta Fish Fight?”, 8 Aug. 2018,



You see right through me

The specimen pictured in this meme is the larval form of an eel, from the suborder Elopomorpha. There are many species of eels that have transparent larva, including the conger, moray eel, and the garden eel. These larvae are transported throughout the ocean by currents from their spawning grounds to intertidal areas, where they morph into their adult form (Science Direct, 2021). Once in their adult forms they do not have the same transparent physical characteristic.

“Leptocephalus Larvae.” Leptocephalus Larvae – an Overview | ScienceDirect Topics,


George, Britain’s Oldest Goldfish, Dies at 44


In 1974 a man by the name of Keith Allies, won two goldfish at a fair and named them Fred and George. Little did he know, the fish would become his companions for the next 44 years of his life. Keith was able to share many monumental milestones with his two fish friends, including his marriage, moving into his first home, and becoming a first time father. Sadly, Fred passed away in 2017, which led to the decline of health in his friend, George, who passed away two years later, in 2019 (Middleton, 2019). Throughout their lifetime, these two old fishy souls have been mascots of the community, and one can argue, for all of Britain.

The real question is, how did those fish live for so long. It is known that most animals who live in captivity live longer lives than those in the wild but 44 years is a longgg time. Scientists and pet enthusiasts have given some helpful tips on how to extend your fish friend’s life including:

  • Use the largest tank possible
  • Provide enrichment for the fish
  • Increase oxygen diffusion into the water
  • Keep tank clean
  • Allow water temperature to change as seasons change
  • Properly feed your fish (Robert, 2021)

RIP George and Fred


Middleton, Lucy. “George, Britain’s Oldest Goldfish, Dies Aged 44.” Metro,, 15 Apr. 2019,

Robert. “How Long Do Goldfish Live? 5 Ways to Increase Their Lifespan.” Fishkeeping World, 28 Sept. 2021,